WaPo: Court asks: Do police need a warrant to track your cellphone for months at a time?

WaPo: Court asks: Do police need a warrant to track your cellphone for months at a time? by Ann E. Marimow:

Law enforcement officials have long relied on location details gleaned from cellphone towers as a powerful tool for tracing steps of suspects, particularly in the early stages of investigations. But civil liberties groups and privacy advocates are increasingly challenging the practice throughout the country, concerned that police and federal agents too easily tap vast caches of information about people’s movements through the devices most Americans carry in their pockets — tracking that could show how often someone goes to a doctor’s office, to a casino or to church.